Tympanopleura brevis (Steindachner, 1881)

Walsh, Stephen J., Ribeiro, Frank Raynner Vasconcelos & Py-Daniel, Lúcia Helena Rapp, 2015, Revision of Tympanopleura Eigenmann (Siluriformes: Auchenipteridae) with description of two new species, Neotropical Ichthyology (Neotrop. Ichthyol.) 13 (1), pp. 1-46 : 19-20

Tympanopleura brevis (Steindachner, 1881) Figs. 1b , 6c , 11

Ageneiosus brevis Steindachner, 1881: 16-17 [type-locality: Amazonenstrom bei Coary (=Coari) und aus dem Hyavary (=Javari), collection date unknown, F. Steindachner; syntypes NMW 47801, 2]. -Eigenmann & Eigenmann, 1888: 149 [checklist]. - Eigenmann & Eigenmann, 1890: 300-302 [in key; citations; description]. - Eigenmann & Eigenmann, 1891: 35 [checklist]. -Eigenmann, 1910: 397 [checklist]. - Miranda Ribeiro, 1911: 402-404 [in key; description]. - Gosline, 1945: 24 [checklist]. - Fowler, 1951: 452 [checklist; citations]. - Burgess, 1989: 286 [checklist]. -Pacheco et al., 2001: 33 [habitat and community assemblage; trophic category; in table; identification not verified]. - Ferraris, 2003: 471 [checklist; synonymy after Walsh, 1990; type-locality; syntypes]. - Pouilly et al., 2003: 1143, 1154 [diet; identification not verified]. -Pouilly & Rodriguez, 2004: 251 [in table; habitat occurrence and abundance in floodplain lakes of Mamoré River, Bolivia; diet, zooplanktivory; identification not verified]. - Pouilly et al., 2004: 251 [in table; río Mamoré; floodplain lakes and edge; identification not verified]. -Granado-Lorencio et al., 2005: 518 [occurrence in Amazonian floodplain lakes; in tables; identification not verified]. - Mojica et al., 2005: 204 [checklist; Colombian Amazon; ICNMHN cataloged lots (4465, 8500); identifications not verified]. -Bogotá-Gregory & Maldonado-Ocampo, 2006: 82 [checklist; Colombian Amazon, after Mojica etal., 2005]. - Ortega et al., 2006: 107 [checklist; source, Duque & Patiño, 2000; common name; Putumayo River basin, Colombia and Peru]. -Akama & Sarmento-Soares, 2007: 116 [checklist; type-locality; distribution]. - Ferraris, 2007: 69, 550, 561 [type checklist; information duplicated from Ferraris, 2003]. -Granado-Lorencio et al., 2007: 687 [in table; see Granado-Lorencio et. al., 2005]. - Hercos et al., 2007: 46 [in list of material cataloged into IDSM collection; collection locality not given; identification(s) not verified]. - Lucinda et al., 2007: 81 [in table; rio Tocantins; influence of hydroelectric reservoir; identification not verified]. -Maldonado-Ocampo et al., 2008: 208 [checklist; Colombian Amazon, after Mojica et al., 2005, Bogotá-Gregory & Maldonado-Ocampo, 2006, Ortega et al., 2006; identification(s) not verified]. -Barriga-Salazar, 2012: 115 [checklist (as A. cf. brevis ); Ecuador, Napo-Pastaza “ichthyohydrographic” zone; identification not verified]. - Birindelli et al., 2012: 5-6, 8-10, fig. 6 [MZUSP 52620, 1 specimen in material examined, identification not verified, but 2 specimens listed in material examined for A. atronasus cited with same catalog number, and most of lot identified as T. atronasus in our study; photographs of gas bladder of MZUSP 34417 identified as A. brevis presumed erroneous and based on T. longipinna ; MZUSP 48966 in material examined, identification not verified]. - Birindelli, 2014: 543 [phylogeny of Doradoidea; MZUSP 34417 in material examined presumed erroneous and based on T. longipinna ; MZUSP 56660 in material examined presumed erroneous and based on T. rondoni ]. Tympanopleura alta Eigenmann & Myers in Myers, 1928: 85 [type-locality: Peru, río Marañon; type IU 15790 (=CAS 58258)]. -Fowler, 1941: 470 [checklist]. -Eigenmann & Allen, 1942: 139-140, plate 6, fig. 4 [types listed; redescription; no coeca (=terminal diverticula) on gas bladder noted, presumably an erroneous observation]. -Fowler, 1945: 67 [checklist; citations]. - Gosline, 1945: 26 [checklist]. - Fowler, 1951: 456, fig. 483 [checklist; citations; distribution]. -Ortega & Vari, 1986: 14 [checklist; citations; common name ( Peru)]. - Burgess, 1989: 285-286 [checklist; illustration after Fowler, 1951]. - Ferraris, 2003: 471 [checklist; as synonym of A. brevis after Walsh, 1990; type-locality; holotype]. - Ferraris, 2007: 68 [type checklist; as synonym of A. brevis after Walsh, 1990; information duplicated from Ferraris, 2003].

Diagnosis. Tympanopleura brevis is distinguished from congeners by having a greatly flattened snout with an acute, upwardly inflected dorsal profile of the head, and the usual presence of a robust, triangular, and rugose postcleithral process (vs. absent or very weakly developed). Tympanopleura brevis further differs from T. atronasus in having a greater number of anal-fin rays (31-36 vs. 23-30), pectoral-fin rays (10-12 vs. 7-9), and gill rakers on the first arch (20-24 vs. 14-18), fewer preanal vertebrae (14-15 vs. 16- 19), fewer pairs of pleural ribs (5 vs. 7-8), greater distance between pectoral- and dorsal-fin origins (21.4-27.0% SL vs. 15.7-20.9% SL), and generally diffuse pigmentation over the head and body, lacking the distinctive dark concentration of melanophores usually present in T. atronasus on the chin, flanks above the anal fin, and streaks in each lobe of the caudal fin. Tympanopleura brevis differs from T. cryptica in having a greater number of anal-fin rays (31- 36 vs. 23-30), pectoral-fin rays (10-12, mode 11 vs. 8-10, mode 9), and more total vertebrae (38-41, mode 40 vs. 38). Tympanopleura brevis differs from T. longipinna in having fewer anal-fin rays (31-36, mode 33 vs. 32-42, mode 37) and total vertebrae (38-41, mode 40 vs. 40-43, mode 43), a longer pectoral-fin spine (19.1-24.4% SL vs. 15.9-18.2% SL), shorter anal-fin base (26.6-33.9% SL vs. 33.9-39.9% SL), and shallower head depth at midpoint of the supraoccipital (43.0-55.6% HL vs. 53.0-74.1% HL). Tympanopleura brevis differs from T. piperata in having fewer anal-fin rays (31-36, mode 33 vs. 31-38, mode 35), greater number of pectoral-fin rays (10-12, mode 11 vs. 6-10, mode 9), gill rakers on the first arch (20-24, mode 23 vs. 16-23, mode 19), and pleural rib pairs (5 vs. 4-5, mode 4), greater predorsal length (35.1- 44.0% SL vs. 28.8-34.4% SL), prepelvic length (47.4-53.9% vs. 41.3-47.0% SL), prepectoral length (27.9-35.6% SL vs. 23.6-28.3% SL), distance between pectoral- and dorsal-fin origin (21.4-27.0% SL vs. 15.2-20.9% SL), and body width at the pectoral-fin origin (20.5-26.6% SL vs. 16.8-20.0% SL), a longer pectoral-fin spine (19.1-24.4% SL vs. 13.9-18.1% SL), longer head (29.7-35.6% SL vs. 22.2-27.8% SL), shallower head depth at midpoint of the supraoccipital (43.0-55.6% HL vs. 54.3-69.7% HL), greater gape width (44.9-57.5% HL vs. 34.8-53.6% HL), smaller eye diameter (13.8-21.0% HL vs. 24.3-35.7% HL), presence of short posterior diverticula on the gas bladder (vs. diverticula absent), and lack of an hourglass-shaped transverse bar of pigmentation usually present at the base of the caudal fin in T. piperata . The relatively uniform pigmentation pattern on the head and body of T. brevis distinguishes it from T. rondoni , which characteristically has a pigmentation pattern consisting of discrete, irregular, large spots distributed over the head, body, and fins. Tympanopleura brevis further differs from T. rondoni in having more anal-fin rays (31-36, mode 33 vs. 28-37, mode 31), fewer gill rakers (20-24, mode 23 vs. 24- 33, mode 29-30) more pleural rib pairs (5 vs. 4-6, mode 6), a larger eye diameter (13.8-21.0% HL vs. 8.4-17.0% HL), and a cordiform gas bladder with shorter posterior diverticula (vs. gas bladder elongated antero-posteriorly and with two longer, recurved posterior diverticula).

Figures

Fig. 1. Dorsal and ventral head profiles of species of Tympanopleura: (a) T. atronasus, INHS 106400 (82.4 mm SL); (b) T. brevis, ANSP 194010 (63.3 mm SL); (c) T. cryptica, INHS 40163 (84.9 mm SL); (d) T. longipinna, MZUSP 114000 (73.0 mm SL, holotype); (e) T. piperata, ANSP 194022 (45.6 mm SL); (f) T. rondoni, ANSP 194015 (75.3 mm SL). Scale bars: a-d, f = 1 cm; e = 5 mm.

Fig. 6. Gas bladders of species of Tympanopleura in ventral view: (a) T. atronasus, INHS 106400 (79.9 mm SL); (b) T. atronasus, FMNH 93488 (107.3 mm SL); (c) T. brevis, SIUC 39913 (59.4 mm SL); (d) T. cryptica, INHS 40163 (60.5 mm SL); (e) T. longipinna, MZUSP 34417 (50.5 mm SL); (f) T. piperata, ANSP 194019 (42.5 mm SL); (g) T. rondoni. MZUSP 7862 (117.6 mm SL). Scale bars: a-e = 5 mm; f = 2 mm; g = 10 mm.

Fig. 11. Tympanopleura brevis, ANSP 194010 (68.5 mm SL), prenuptial male, rio Jutai, Amazonas State, Brazil.